static int eio_AfterConnect(eio_req *req) {
    printf("eio_AfterConnect; rc = %d\n", req->result);
    ev_unref(EV_DEFAULT_UC);
  }

  static int eio_Connect(eio_req *req) {
    // Note: this function is executed in the thread pool! CAREFUL

    int *foo = (int*)(req->data);
    printf("** %p\n", foo);

    // this should print 420 but segfaults instead
    printf("** %d\n", *(int*)(req->data));

    req->result = 666;
    return 0;
  }

  static Handle<Value> Connect(const Arguments& args) {
    HandleScope scope;

    int *foo = (int *) malloc(sizeof(int));
    *foo = 420;

    printf("foo is %d\n", *foo);

    eio_custom(eio_Connect, EIO_PRI_DEFAULT, eio_AfterConnect, foo);
    ev_ref(EV_DEFAULT_UC);

    return Undefined();
  }